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echinoderm
No. They are invertebrates related to starfish and sea urchins.
Sand dolar is a simple animal. It is an invertebrate.
Sand dollars a rigid skeleton called a 'test' (which is basically a shell).
Sand dollars has a rigid skeleton known as a "test", but these are not backbones so they are invertebrates. Vertebrates are animals that have spinal chords, heads and backbones. Sand dollars are animals related to sea urchins, in a different group called Echinoids. These have none of spinal chords, heads or backbones, so cannot be vertebrates.
Sand fish eat small invertebrates, especially millipedes.
In the sand
You can not cheat to get sand dollars. You have to work for it, or you have to buy it.
Sand dollars.
Sand dollars breathe through a process known as diffusion, using their tube feet.
sand dollars got there name because they are shaped like a coin and they dig themselves into the sand
Sand dollars don't protect themself, they just sit their........ :)-